Final answer:
Child labor was prevalent due to economic necessity among families, low cost to employers, lack of social safety nets, and delayed enforcement of legislation aimed at education and labor restrictions.
Step-by-step explanation:
The extensive use of child labor was spawned by a confluence of factors during the industrialization period. Families often depended on the income that children could provide, which was critical for their survival, especially among the working class and immigrant populations. Employers found them desirable labor because they could be paid much less and were small enough to fit among machines or perform tasks adults could not.
Additionally, political resistance and the need for inexpensive labor led to a slow implementation of legislation that would protect children. This was exacerbated by the lack of social safety nets such as unemployment insurance or health benefits and the absence of compulsory education laws.
Eventually, laws mandating schooling and restricting child labor would lead to a decrease in its prevalence, but this did not occur uniformly until well into the 20th century.